Another, and an even better-known philosopher, Des Cartes, is said to have been a friend of Newcastle. Surely Walpole was too severe when he accused a companion of Des Cartes and Hobbes of “accommodating his mind to the utmost idleness of literature”.
Newcastle seems to have made scientific experiments on his own account. In a Preface which he wrote to his wife’s Philosophical and Physical Opinions, he says: “Dr. Payne, a divine and my chaplain, who hath a very witty, searching brain of his own, being at my house at Bolsover, locked up with me in a chamber to make Lapis Prunellae, which is saltpetre and brimstone[168] inflamed, looking at it a while, I said, Mark it, Mr. Payne, the flame is pale like the sun and hath a violent motion in it, like the sun; saith he, It is so, and the more to confirm you, says he, look what abundance of little suns, round the globe, appear to us everywhere, just the same motion as the sun makes in every one’s eyes. So we concluded the sun could be nothing else but a very solid body of salt and sulphur, inflamed by his own violent motion upon his own axis.”
[168] The ingredients of gunpowder, minus the charcoal.
So much for scientific inference. But observe what presently follows:—
“This,” he concludes, “is my opinion, which I think can as hardly be disproved as proved; since any opinion may be right or wrong, for anything that anybody knows, for certainly there is none can make a mathematical demonstration of natural philosophy”.
Well! The exact sciences have advanced a little since such a statement as that could be made.
MARGARET, DUCHESS OF NEWCASTLE
From the frontispiece of one of her books by Diepenbeck